Hovering is a technique that uses the Pegasus Boots to cross pits similar to bomb jumps. Hovering is not limited in distance however. One may hover as far as their endurance/skill can allow them to.
Additional Information on how to perform a hover can be found on the ALTTP Speedrunning Wiki's hovering page.
Moldorm II Hover
Hookshot Cave Hover
You can use hovering to get the items in Hookshot Cave without the Hookshot. The gif above demonstrates the ideal order to clear these chests. Clear the bonkable chest first, then hover to the left after killing the blue bari. Use the chest to bonk to the left. Use the pot on the north end of this platform to bonk to the right. Open the third chest (No hovering is required to go from the second to the third chest). Lastly, hover to the right for the last chest.
Palace of Darkness Ledge Hover
You can hover to the Ledge Chest in Palace of Darkness. This sequence breaks the bow-locked side of PoD. This accomplishes the same thing as Potion Camera Unlock and Mimic Clip. Due to the pixel-perfect x-coordinate that's required to execute this hover, this is one of the more difficult hovers in the game.
"God Mire" Hover
If the Big Key is in the bridge chest of Misery Mire, you can hover over to the bridge on the right to bypass having to backtrack in mire. When the Mire Big Key is in this chest (which is typically checked first), it's referred to as "God Mire" because you can go straight to Vitreous without opening any other chests.
Mire Big Key Room Hover
If executed properly, this hover is a quicker path back to the Misery Mire lobby. You must have your sword out to execute this glitch and you must be on a specific y-coordinate to properly clip into the rail. This is arguably one of the most difficult/skillful hovers one can perform.
East Death Mountain Fairy Revival Hover
On Death Mountain, it is possible to hover across the bridge. You must jump holding a bomb and kill link mid air. When the fairy revives you, you MUST press the A button on the FIRST frame that link spawns. If you are holding it before or press the button even one frame after, Link will fall in to the pit. If you press the A button on the correct frame, it's just a regular hover beyond that point.
P-Train's video: On Hovering